A one-year transitional arrangement was signed by the previous government last year, but Ms Stevens says service providers need to know as soon as possible if a new agreement will be put in place.

"Already we're seeing a great deal of stress amongst service providers, staff are actually looking around and leaving and finding other employment because they're uncertain as to whether their job will still exist in a few months' time," she said.

"This in turn is impacting on the clients because they're not receiving the support they should be receiving."

No evidence Government in negotiations for new funding: Greens

The Greens spokesman on housing, Senator Scott Ludlam, says the Government cannot afford to wait until the budget in May to announce whether it will fund a new agreement.

"It's imperative the Government doesn't wait until the budget to get this sorted out," he said.

The Minister talked about leadership in housing and homelessness policy. By withdrawing the funding lever, that leadership is dissipating."

Labor Senator Jan McLucas

He says there is no evidence the Government is in negotiations with the states and territories for a new round of funding, and he agrees that it is already having an impact on services.

"What we know is happening behind the scenes is nothing, and it's not the fault of the states and territories as far as we can tell," he said.

"I'm aware of homelessness services that are closing their doors this month and will be laying people off if the funding agreement can't be secured.

"You can't keep staff on if you don't know how you're going to be able to employ them in a few months' time."

The Federal Opposition says evidence at Senate estimates hearings also showed the Commonwealth is not negotiating a new agreement.

"There have been no negotiations with states and territories around the National Partnership Agreement on Homelessness, about how it would be rolled out," said Labor's spokeswoman, Senator Jan McLucas.

She says if the Government is intending to roll over the agreement for another year it should be announced as soon as possible.

"The Minister talked about leadership in housing and homelessness policy," Senator McLucas said.

"By withdrawing the funding lever, that leadership is dissipating."

Social Services Minister Kevin Andrews declined the ABC's requests for an interview about the future of the NPAH.

Editor's note: This story has been updated to amend references to the amount of funding the NPAH has provided since 2009.